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Publication numberUS3163196 A
Publication typeGrant
Publication dateDec 29, 1964
Filing dateApr 3, 1961
Priority dateApr 3, 1961
Also published asDE1400838A1, US3186464, US3192819
Publication numberUS 3163196 A, US 3163196A, US-A-3163196, US3163196 A, US3163196A
InventorsWalter M Hanneman
Original AssigneeIllinois Tool Works
Export CitationBiBTeX, EndNote, RefMan
External Links: USPTO, USPTO Assignment, Espacenet
Preassembled fastener unit with elliptical threads
US 3163196 A
Abstract  available in
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Claims  available in
Description  (OCR text may contain errors)

D 1964 w. M. HANNEMAN PREASSEMBLED FASTENER UNIT WITH ELLIPTICAL THREADS Filed April 3, 1961 INVENTOR. 756m BY %Mf/% United States Patent O" 3,163,196 PREASSEMBLED FASTENER UNIT WITH ELLIPTICAL TIREADS Walter M. Hanneman, Wheaten, BL, assignor to Illinois Tool Works Inc., a corporation of Delaware Filed Apr. 3, 1961, Ser. No. 1%,224 2 Claims. (Cl. 151-37) The present invention relates to a novel preassembled fastener unit and method for making the same, and more particularly to a novel preassembled fastener unit of the type comprising a screw and a washer telescopically associated with the screw shank.

An important object of the present invention is to provide a novel preassembled fastener unit and method of producing the same whereby the parts thereof such as a screw and a washer may be easily and economically assembled with each other and secured in such assembled relationship.

A more specific object of the present invention is to provide a novel fastener unit and method of producing the same of the above described type whereinincreased clearances may initially be provided for facilitating assembly of the parts and subsequent relative rotation therebetween while at the same time, the parts may be securely retained in assembled relationship.

Other objects and advantages of the present invention will become apparent from the following description and the accompanying drawings, wherein:

FIG. 1 is a partial sectional view showing a unit incorporating features of the present invention in a finished condition;

FIG. 2 is a fragmentary view similar to FIG. 1, but shows the unit in a partially completed condition;

FIG. 3 is a sectional view taken along line 33 in FIG. 1;

FIG. 4 is a sectional view taken along line 4+4 in FIG. 2;

FIG. 5 is an enlarged fragmentary View similar to FIG. 4 and shows certain features of the present invention in greater detail;

FIG. 6 is a sectional view showing one step in the process of securing the parts of the fastener unit in assembled relationship in accordance with the present invention; and

FIG. 7 is a fragmentary plan View showing a portion of the die structure used for carrying out the present invention and shown in FIG. 6.

Referring now more specifically to the drawings wherein like parts are designated by the same numeral throughout the various figures, a fastener unit 10 incorporating features of the present invention is shown in FIGS. 1, 3 and 5. The unit ltl includes a threaded rotary fastener member or screw 12 and a lock Washer 14.

The screw member is provided with a head portion 16 which may be of any desired construction presenting a generally radially extending clamping face 18. A shank portion 26 extends axially from the head portion 16 and telescopically receives the washer 14. The shank portion is formed in accordance with features of the present invention described in detail below for retaining the washer in assembled relationship therewith.

In the embodiment shown for the purpose of illustrating the present invention, the washer 14 includes an annular body portion 22 having an inner margin 24 of predetermined diameter. A plurality of twisted teeth or prongs 26 is provided, which prongs extend from integral junctions with an outer margin of the body 22 and are substantially equally spaced therearound. The prongs 26 are twisted about their respective radial axes so as to present tooth edges 28 and 30 axially of opposite sides of the body portion 22 for engagement with the clamping 36 of the shank immediately adjacent the head portion 3,163,196 Patented Dec. 29, 1 964 surface 18 of the screw head portion and a work structure when the fastener unit is applied to the work structure. However, it is to be understood that various different types of lock washers may be utilized in the unit of the present invention, and such different lock washers might, for example, have prongs or teeth extending radially inwardly'rather than radially outwardly.

When producing the unit 10 in accordance with the present invention, the washer 14 is telescoped over the shank 20 of the screw member while the shank is in a smooth or unthreaded condition as shown in FIGS. 2 and 4. It is to be noted that the internal diameter of the Washer is substantially greater than the diameter of the unthreaded screw shank so that there is a very substantial clearance 32 between these parts. This substantial clearance greatly facilitates the alignment and telescopic assembly of the washer and shank portion 29 and subsequently promotes freedom for relative rotation between the screw and the washer during application of the fastenet unit to a work structure.

' In order to retain the washer in assembled relationship with the screw member, the shank portion 26 is rolled, in accordance with features of the present invention so as to provide helical thread convolutions 34 thereon beneath the washer. in the manner described in detail below so as to project beneath and retain the washer on an unthreaded portion clamping face 18.

As shown in FIGS. 3 and 5, the thread convolutions 34 are formed so that a first pair of diametrically opposite portions 38 and 40 thereof project radially outwardly of the surface of the unthreaded portion 36 of the shank and also outwardly of the inner margin 24 of the washer so as to underlie and retain the washer. However, a second pair of diametrically opposite portions 42 and 44 of the thread convolutions project radially a distance less than the projection of the thread portions 38 and 40 so as to lie within the inner margin 24 of the washer. In other words,'the thread convolutions are formed so as to have a generally elliptical or oval transverse cross section as shown in FIGS. 3 and 5, which cross section has a major axis bisecting the thread portions 38 and 40 and greater in extent than the internal cular transverse cross section having a diameter substantially less than the internal diameter of the washer so that the washer remains freely rotatable relative to the screw member.

In order to produce the unit 10 in accordance with the present invention, the washer is assembled with the unthreaded shank in the manner described above whereupon the thread convolutions 34 are rolled on the shank with the aid of dies 46 and 48 shown in FIGS. 6 and 7. Each of the dies 46 and 48 is provided with a plurality of ribs 50 defining grooves 52 therebetween, which ribs and grooves extend generally longitudinally and diagonally of the dies. In accordance with the present invention, the crests of the ribs are hollowed out or dish shaped between spaced points 54 as shown best in FIG. 6. The distance between the points 54 is approximately equal to the circumferential extent of the roots of the thread convolutions between points defined by intersections of the major axis of the elliptical cross section with the roots. Withthis structure, the thread convolutions will be formed with the above described generally elliptical These thread convolutions are formed -cross section when the screwshank is rolled bet-Ween' the die blocks 46 and 43; In order to accomplish the rolling operation, the screw shank is inserted between the die blocks in any suitable or known manner where- 3 upon the blocks are relatively shifted with respect'to each other in the direction of the arrows in FIGL:;6. 1

While the preferred embodiment of the present invention has been shown'and described herein, it is obvious that many details may be changed Without departing from the spirit and scope of the appended claims.

. 1' The invention is claimed as follows:

1. A preass'embled fastener unit comprising a screw having means presenting a clamping surface and a shank portion extending axially from said clamping surface, and an annular washer telescopically associated with said washer including means defining a substantially circular :diarrieter, 'said lock washer: including' an annular body section and a plurality of prongs circumferentially spaced around and extending generally radially from an edge of said annular body section, said prongs being twisted about their radial axes and respectively presenting toothedges axially of opposite sides of said body section for engage- 1 ment with said clamping surface and a surface of a work.

'15 shank portion and disposed adjacent said surface, said inner margin having a predetermined diameter, said shank portion including a smooth unthreaded substantially circular section adjacent said surface having a diameter substantially less than said predetermined diameten'and,

structure when the fastener unit is applied to the work structure,3said shank, including a smooth unthreaded substantially circular section adjacentsaid clamping surface having a diameter substantially less than said predetermined diameter, and said shank portion including helical thread convolutions extending'continuously axially outwardly from said shank selection substantially to an" entering end of the shank, all of said thread convolutions including continuous, uninterrupted crests having a generally elliptical cross sectional configuration, at least one of said thread convolutions immediately adjacent said sec-3 tion having major and minor crest axes respectively greater than and less than said predetermined diameter,

- for presenting diametricallyopposite portions thereof for said shank including helical threadconvolu'tions extend ing substantially continuously axially outwardly from said shank section substantially to and entering end ofsaid a shank, all of said helicalthread convolutions having crests which are continuous and generally'elliptical in cross'seo tional configuration, one of saidifthread convolutions immediately adjacent said shank "section having a major crest axis substantially greater than said predetermined diameter and a minor crestjaxis less than said predeter= mined diameter for presenting diametrically opposite porwasher for retaining the washer on* said shank section.

tions thereof for engagementcbeneath saidmargin of the 2. A preassembled fastener unit vcomprising a screw having a head portion presenting a clamping sunface and a shank portion extending axially from-said clamping surface, and an annular 'lock washer telescopically asso ,ciated with said shank portion and disposed adjacent said surface, said lock washer; including means defining a'substantially circular inner margin having a predetermined engagement beneath said margin ofthe washer for retaining'the washer on said shank section.

i i References Cited by the Examiner UNITED STATES PATENTS Crowther e 151 37 EDWARD ALLENJi-iindr Examiner.

CARL W. TOMLIN, Examiner.

Patent Citations
Cited PatentFiling datePublication dateApplicantTitle
US2113424 *Mar 2, 1936Apr 5, 1938Illinois Tool WorksScrew and lock washer assembly
US2289066 *Jan 4, 1940Jul 7, 1942Illinois Tool WorksFastener unit
US2343798 *Jul 1, 1939Mar 7, 1944Illinois Tool WorksScrew and washer assembly machine
US2352982 *Jun 25, 1942Jul 4, 1944American Screw CoScrew for plastics
US2414870 *Sep 14, 1943Jan 28, 1947Edmund J LadaFastening device
US2672069 *May 21, 1952Mar 16, 1954Mitchell RobertScrew and washer assembly
US2779376 *May 4, 1955Jan 29, 1957Illinois Tool WorksFastener having folded, split-ring helical lock washer retained thereon
US2946039 *Nov 6, 1957Jul 19, 1960Durakool IncElectrical terminal
US2965146 *Oct 24, 1956Dec 20, 1960Illinois Tool WorksScrew and lock washer assembly
US3009176 *Jul 18, 1957Nov 21, 1961Louis T KnockeMethod of assembly of bolt and washer
Referenced by
Citing PatentFiling datePublication dateApplicantTitle
US3346935 *Sep 27, 1962Oct 17, 1967L & L Mfg CompanyMethod of making a fluid pressure coupling
US3398628 *Dec 28, 1966Aug 27, 1968Hi Shear CorpStud assembly with tapered expansion segment
US3452375 *May 10, 1967Jul 1, 1969Eric G GabbeyProcess for producing self-locking screw threads
US3497890 *Aug 31, 1967Mar 3, 1970Threadline Fastener CorpFastener and method of making the same
US3772720 *Mar 22, 1971Nov 20, 1973Res Engine Manuf IncMethod for making a thread forming member
US3800585 *Dec 11, 1972Apr 2, 1974Nl Industries IncDie for forming lobed threads
US3818749 *Oct 2, 1972Jun 25, 1974Nl Industries IncThread rolling dies and method of manufacturing same
US3827268 *Oct 5, 1973Aug 6, 1974Rockford Screw Prod CoApparatus for making self-locking bolts
US3981170 *May 8, 1975Sep 21, 1976Illinois Tool Works Inc.Apparatus for assembling a screw and compressible washer
US4292007 *Nov 7, 1979Sep 29, 1981Illinois Tool Works Inc.Fastener and washer assembly
US4353233 *Jan 29, 1981Oct 12, 1982Amca International CorporationDies for making thread-forming fasteners
US7677851 *Dec 20, 2007Mar 16, 2010Illinois Tool Works Inc.Fastener assembly
US8616818Feb 17, 2011Dec 31, 2013Raytheon CompanyGripping washer having one or more deformable gripping tabs and method for reducing foreign object debris
Classifications
U.S. Classification411/134, 72/88, 29/522.1, 470/50, 411/165, 29/509, 411/959, 470/9, 411/938
International ClassificationF16B39/26, F16B39/24, B21H3/02, F16B25/00
Cooperative ClassificationF16B25/0052, B21H3/027, Y10S411/938, F16B39/26, F16B25/0047, Y10S411/959, F16B25/00, F16B25/0021, F16B39/24
European ClassificationF16B25/00G1B, F16B25/00C2, F16B25/00G1A, F16B39/24, F16B39/26, F16B25/00, B21H3/02S